1
\$\begingroup\$

I am designing an ideal diode circuit for back EMF protection and reverse polarity protection outputting on average 60 A from a 4s9p li-ion battery to run 8 motors.

For this circuit, I used an LTC4372 as an ideal diode controller to control 2 MOSFETs as following (ignoring 2UPU and SHDN pins I use for my purpose in other schematics):

enter image description here

Normally, I would have several of the above circuits in parallel for current sharing.

enter image description here

I am not too sure and a bit curious if multiple back-to-back MOSFETs can be connected in parallel like in the configuration below:

Parallel MOSFETs

\$\endgroup\$

1 Answer 1

1
\$\begingroup\$

Multiple MOSFETs in parallel behave exactly like one large MOSFET due to the positive temperature coefficient of the on resistance (on resistance goes up with temperature, thereby ensuring proper current sharing).

As long as your controller can drive the combined gate charge of the parallel MOSFETs, this will work just fine.

You should not give each MOSFET its own gate resistor, though. Instead, parallel the MOSFETs directly (gate, source, and drain terminals directly connected) and only give the overall parallel MOSFETs a single gate resistor to ensure that the gate voltage of all of them is always equal.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.